Formation tester and sampler



March 13, 1951 R. o. POLLARD, .JR 2,545,306

FORMATION TESTER AND SAMPLER Filed Sept. 24, 1949 2 Sheets-Sheet 1INVENTO 274102 4 Pad are,

ATTORNEYS March 13, 1951 R. o. POLLARD, JR

FORMATION TESTER AND SAMPLER 2 Sheets-Sheet 2 Filed Sept. 24, l949INVENTOR. F0460? Q Pad era, 4/ Q MWM ATTORNEYS Patented Mar. 13, 1951Robert 0. Pollard, Jr., Downey, Calif., assignor tolRichfield OilCorporation, Los Angeles,0alif., a corporation of Delaware ApplicationSeptember 24, 1949, Serial No. 117,660

2 Claims.

My invention relates to improvements in equipment for taking samples offormation and formation fluids from well boreswells for production ofoil and gas particularly. Thework of the production engineer improves ashis knowledge of the formations in' which he is working increases, asthis knowledge becomes more complete and more dependable." The factorsinvolved include permeabilities: and porosities of the formations,composition of formation fluids and formation pressures; The advantagesof my in vention resides particularly in the ease, speed and economywhich dependable samples of formation and of formation fluids can betaken and recovered for examination and analysisand, therefore, in thevery completev data which, with my invention, can be obtained in shortorderzand at reasonable cost for a well or group of wells or aproductive area.

My invention comprises a 'tester'sampler adapter to be lowered through awell bore which, at a predetermined position in-the well bore, willtake, simultaneously, a sample of the formation and, under formationpressure, a sample of the fomation fluids and which will retain thosesamples, that of the formation under formation pressure, as'thetester-sampler is withdrawn through the well bore with a minimum ofcontamination, for example with mnds or other drilling fluids used fordrilling or sealing ofithe walls of the bore.

The formation tester and sampler of my in- "vention consists essentiallyof a body member adapted to be lowered through a well bore with its longaxis approximately coincident with that of the well bore, a base memberpositioned within the body member and pivoted the-reinon. an axis normalto the long axis of the bod memher, a projectable tubular member open atits outer end carried by the base member which,

when retracted with its axis of projection normal to the long axis ofthe'body member, lies within the body member and which, when extendedwith its axis of projection normal to "the long axis of the body member,projects beyond the body memher in a plane approximately normal to theaxis of the well bore, a recess in the body member adapted to receivethe projectable member when extended with said base member turned sothat the axis of projection of the suspended projectable memberisapproximately parallel to the lon axis of the body member, power meanscarried by the body member for driving the :projectable member into theformation around the well bore in a plane approximately :normaltothetaxis of (Cl. 255I.4)

2 the well bore when the body member is'in predetermined position withinthe well bore,'-and means for releasing the projectable member to permitwithdrawal of the body member through thewell bore. 1

The formation tester and sampler of my invention also comprises, withadvantage, a chamber carried by the body member for receiving a sampleof formation fluids through a connection opening into the interior ofthe projectable tubular member, means for opening this connection afterthe open end of the projectable member has entered the formation andmeans for closin this connection after the projectable member h'asbe'enextended and before: it is withdrawn'fromth e formation. 1.

The formation tester and sampler of m 'invention can be lowered into thewall bore 'on a wire line, particularly where speed is important aswhere samples are to be taken at a number of horizons, or it can belowered on a run-in string of tubing or drill pipe, as where a,production test of some duration is to be run on one or more of anyproducing formations penetrated by the well bore. In such cases, theconnection opening into the interior of the projectabl member isarranged to communicate with the lower end 0f the tubing or drill piperather than the sample chamber carried by the body member of; thetester-sampler.

To facilitate understanding of my invention, 1 will described it furtherby reference to theaccomp anying drawings illustrating, diagrammatrically and conventionally, two embodiments of my improvedtester-,sampler,v and its general mode of operation, but it will beunderstood that this detailed exemplification is by way of illustration,not limitation, of the invention above stated. Inthese drawings:- 7Figs. 1, 2 and 3 are fragmentary representations, the first twoisometric and the third in elevation, with parts broken away, of theupper, middle and lower portions, respectively, of-a tester-samplerembodying ,my invention. Fig. 4 is a similar isometric representation,corresponding generally to Figs.v 1, 2 and 3, taken together with thedetail of Fig. 2' omitted, of a modified tester-sampler embodying myinvention; I

Fig. 5 is a section on the line 5-45 and Figs ,6 and '7 illustrate, asviews in elevation and partly in. section and with parts broken of Fig,11;

away, the-operation of, tester-samplers, such as 3 those of thepreceding figures, embodying my invention.

Although my invention is a combination of elements in a particularrelationship, I will refer first to Figs. 6 and 7 which illustrate themode of operation of one of the characteristic elements of thetester-sampler of my invention, some details of which in particularembodiments are also shown in Figs. 1 and 5. The assembled forma tiontester and sampler is lowered through the well bore by means of 2, tothe horizon at which samples are to be taken with the base member II inthe position illustrated in Fig. 6 but with the projectable membercomprising elements 25 and IE retracted as shown in Fig. 1. With thetester-sampler in position, the operation proceeds in a sequence ofsteps timed either through one or more control conductors extendingtothe surface or by means of a control timer carried by thetester-sampler. First, the projectable member is driven into theformation. The open end of the projectable member may be initiallycovered with a sheet of appropriate plastic mechanically destroyed asthe projectable member is extended, to exclude fluids before theprojectable member is extended. Since, as the projectable member isextended, it moves in a plane approximately normal to the axis of thewell bore, the entering edge of the advancing tubular memberestablishesa seal excluding fluids other than for- .mation fluids,drilling muds for example, as soon as it begins to encounter resistancefrom the formation. With the projectable member fully extended, aformation samplesimilar to a core sample fllls the outer part of theextended tubular member I6. As the projectable member reaches the limitof its extension, or shortly thereafter, connection I9 between theinterior of the extended tubular member, and thus the formation, and asample chamber carried by the tester-sampler is opened to permitthetaking, through the extended projectable member, of a sample offormation fluids under formation pressure.

pressure, or, for example, it may be charged with nitrogen to somepredetermined pressure. Then, either before the tester-sampleisretracted or as withdrawal of the tester-sampler begins, this connectionI9 is closed to retain the sample of formation fluids as taken. Also,before the testillustrated in Fig.v 1, to permit recovery forexamination and analysis of the samples thus taken of the formation andof the formation fluids. Pressurerecording devices or temperaturerecording devices or both, responsive to the pressure and temperature ofthe formation fluids flowing through connection I9, can also be carriedby the tester-sampler.

Now, I will refer more particularly to the embodiment of my inventionillustratedin Figs. 1, 2, 3 and 5. The tester-sampler of my inventioncomprises a body member I adapted to be lowered through a well bore withits long axis approximately coincident with that of the well bore, abase member II positioned within this body member on pivots I2 and I3, aprojectable tubular member comprisin telescopic tubes I and .16, arecess III in the body member I adapted to receive the projectablemember when extended Prior to the opening of this connection, the samplechamber may be at atmospheric with the base member I I turned so thatthe axis of projection of the projectable member is approximatelyparallel to the long axis of the body member, power means comprising thepiston 42 working in the power cylinder 43, and thus through appropriatehydraulic connections and control means, for driving the projectable'memher into the formation around the well bore, and means'for releasingthe projectable member to permit withdrawal of the body member throughthe well bore and for controlling the taking samples of formationfluids. The base member II is chambered to receive the several tubularelements I5, I6, I1 and I8. This chamber 33 connects, hydraulically,with the power cylinder 43 through ducts 34, 35 and 36. The flangedinner ends of these tubular elements 2I, 24 and 21, sealed by means ofrubber rings 22, 25, 28 and 29, move as pistons in the annular spacebetween the cylindrical wall I4 of chamber 33 and the conductor tube I8secured to the inner part of the base member. Retaining ring 23 holdsthe assembly in place. The outer end of tube It is provided with acutting edge 3I, to facilitate entry into the formation, and clearanceis provided by the retreating flanges 32 and 30 on the tubes I5 and I5,respectively. When the axis of projection of the 'projectable member isnormal to the long axis of the body member I, conductor tube i8communicates through port 20 with connection I9. When the base memberII, and thus the projectable member is turned from this position,this'port 20 is closed by revolution of the base member. A rubber seal26 is provided to'make this closure effective. A spring lock comprisingball 38 loaded by spring 31 and recess 39 in the base member I I isprovided to hold the base member in position as the tester-sampler islowered into position. The body member I comprises a center part 5, anupper part 3 of reduced diameter carrying a sample chamber 4 and anypressure or temperature recording devices, and a lower part I carryingthe power means. This center party 5 may carry control elementsin'addition to the base member and projectable member just described. Inthe embodiment illustrated, connection [9 between the conductor tube [8and the sample chamber 4 is also controlled by a pressure actuated valvecomprising piston 10 (accessible through plug 13) which, when thepressure in chamber 69 exceeds that exerted by spring 1|, moves (to theleft in this pressure has been exceeded in the hydraulic system throughwhich the power means operates. Also in this embodiment, means areprovided'for releasing through passage 64 the hydraulic pressure imposedby the power means through connectiion 36 after the power means has beenactuated. These means comprise a frangible disc 65 seated on gasket 66',a projectile 53 to be discharged through plug 6| (seated on gasket 52)and disc 66 and thus into the well bore and at the same time to releaseplug 65 and'a powder charge for discharging this projectile when igniterwire 59 is heated. The power means comprises a piston 42 moving .inpower cylinder -43 and driven vvby piston 41! moving in cylinder. 4!.These pistons are pros vided with appropriate sealing ringsas'indicated. In the embodimentillustrated in Fig. 3 the pisten 40 isactuated by a powder charge 41- in the chamber between'the piston 40when in the lower position defined by the limit rim 45 and the basepistons 4!} and 42 are positioned and casing 44 is secured to the bodymember I, after install- ,ing discs 66 and 68, prior to each testandsampling operation. .Similarly, casing 48, carrying in chamber 52 atiming clock '50 with two adjustable contacts 54 and'55 adapted toclosecircuits through battery 51' and insulated conductors 56 and 58 andthus through wires 51 and 59, respectively, by operation of therevolving contact arm 53, is secured to the lower end of casing 44 afterthe timing clock is set. A sleeve is provided over casing 44 or 48 orboth (or casing 19 in Fig. 4) to protect any control conductors carriedpast the power cylinder externally of casing 44.

In the embodiment illustrated in Fig. 4, instead of actuating the powerpiston 40 with a powder charge, it is actuated by the pressure of theliquid column in the well bore when a projectile firing mechanism 9,similar to 59-63, ruptures frangible disc 16 admitting the liquid tohydraulic begins to increase. First-as the pressure in the chamberincreases, tubular elements l-E- and it are driven into the formation.Next, as the pressure continues to increase and time after these tubularelements have entered the formation, connection lie is openedestablishing communication between the sample chambers and the:formation, under formation pressure, through tubes: Hi, I? and 18. Next,the pressurein the hydraulic system isreleased, by firing of projectile6-3, closing connection l9 and releasing theprojrectable membercomprising tubes F5 and I6. Finally,- the testers-ampler' is pulled tothe surface for recovery of the sample of formationfluids retained in.the sample chamber 4 and the formation sample retained in mbe E6 ortubes t6 and W. As pullout of the tester-samplerbegins the extendedprojectable member swings downwardly, by revolution of the base memberII on the pivots l2 and i3, into the recess in the body member I, thisrevolution also closing connection l9 at port 20. It will be apparentthat this operation, producing a simultaneous sample of formation fluidsand of the same formation, can be completed virtually as quickly as thetester-sampler of my invention can be run in and out of the well bore.Time usually being the most expensive factor in drilling operations, thetester-sampler of my invention thus provides a particularly importanteconomy in making a test or series of the space within casing 19 beneathpiston 40. In

the embodiment of Fig. 4, the power means is put in operation by animpulse transmitted over conductor 11, the release mechanism (59-66) byan impulse transmitted over conductor 18. It will be apparent thateither power means, that of Fig. 3 or that of Fig. 4, or the releasemeans may be controlled by either of such mechanisms and thus bycontrols carried by the tester-sampler or from the upper end of the wellbore.

To drive the power piston 40 in the embodiment illustrated in Fig. 3,conventional slow-burning powders may be used. For example, the powderused in conventional railroad fusees composed of a mixture of carbon andsodium nitrate and sodium perchlorate may be used. In such compositions,the carbon is usually supplied as Wood dust but I prefer to use carbonblack as more uniform and more reliable. The charge of powder isproportioned to the area and travel of the power piston, to deliver,through the hydraulic system, the necessary driving force for extensionof the projectable member into the formation. Satisfactory results areusually obtained with maximum pressures in the power cylinderapproximating 7000 lbs. per square inch, and such pressures areeasilyobtained and controlled with conventional powders.

The mode of operation of the formation tester and sampler of myinvention illustrated in the accompanying drawings is as follows: Thepowder charges 47 and 60 are inserted the frangible discs 66 and 68 (and16 if used) are inserted, the hydraulic system is charged, a cleansample chamber 40 is inserted, and the tester-sampler is assembled withthe base member H and the projectable member in the position shown inFig. l. The assembled tester-sampler is then lowered to the horizon atwhich samples are to be taken on cable 2. With the tester-sampler inposition, the power piston 40 is actuated, by a timing mechanism as inFig. 3 or through a conductor to the surface as in Fig. 4, and pressurein the tests.

I claim:

1. A formation tester and sampler comprising a body'member adapted to belowered through a well bore with its long axis approximately coincidentwith that of the well bore, a base member positioned within said bodymember and pivoted on an axis therein normal to the long axis of thebody member, a projectable tubular member open at its outer end carriedby said base member which, when retracted with its axis of projectionnormal to the long axis of the body member, lies within said body memberand which, when extended with its axis of projection normal to the longaxis of the body member, projects beyond the body member in a planeapproximately normal .to the axis of such Well bore,

a recess in said body member adapted to receive said projectable memberwhen extended with said base member turned so that the axis ofprojection of said projectable member is approximately parallel to thelong axis of the body member, powermeans carried by said'bod member fordriving said projectable member into the formation around the Well borein a plane approximately normal to the axis of the well bore when thebody" member is in position within the well bore, and means forreleasing said projectable member to permit withdrawal of said bodymember through the Well bore. I

2. A formation tester and sampler comprising a body member adapted to belowered through a well bore with its long axis approximately 00-incident with that of the well bore, a base member positioned withinsaid body member and pivoted on an axis therein normal to the long axisof the body member, a projectable tubular normal to the axis of suchwell bore, a recess in said body-member adapted to receive saidprojectable' member when extended with said base member turned so thatthe axis of projection of said projectable member isapproximatelyparallel to the long axis of the body member, power meanscarried by said body member for driving said projectable member into theformation around thewellbore in a plane approximately normal to the axisof the well bore when the body member is in position within the wellbore, a chamber carried by said body member for receiving a sample ofthe formation fluids through a connection opening into the interior ofsaid projectable tubular member, means for opening said connection afterthe open end of said projectable member has entered the formation andmeans for closing said connection after said projectable member has beenextended and before said projectable member is withdrawn 7 from theformation, and means for releasing said projectable member to permitwithdrawal of said body member through the well bore.

ROBERT o. POLLARD, JR; I

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS- 7 Bandy Jan. 1, 1946

